Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
  • F02B37/04—Engines with exhaust drive and other drive of pumps, e.g. with exhaust-driven pump and mechanically-driven second pump
  • F02B37/10—Engines with exhaust drive and other drive of pumps, e.g. with exhaust-driven pump and mechanically-driven second pump at least one pump being alternatively or simultaneously driven by exhaust and other drive, e.g. by pressurised fluid from a reservoir or an engine-driven pump
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
  • F02B37/005—Exhaust driven pumps being combined with an exhaust driven auxiliary apparatus, e.g. a ventilator
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B39/00—Component parts, details, or accessories relating to, driven charging or scavenging pumps, not provided for in groups F02B33/00 - F02B37/00
  • F02B39/02—Drives of pumps; Varying pump drive gear ratio
  • F02B39/08—Non-mechanical drives, e.g. fluid drives having variable gear ratio
  • F02B39/10—Non-mechanical drives, e.g. fluid drives having variable gear ratio electric
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/10—Internal combustion engine [ICE] based vehicles
  • Y02T10/12—Improving ICE efficiencies

Definitions

• the present invention relates to a turbosupercharger of an internal combustion engine in which a rotary electric machine is incorporated on a turbine shaft.
• turbosupercharger for an internal combustion engine
• a turbosupercharger having a rotary electric machine in which the rotary electric machine is incorporated on the turbine shaft, the turbine shaft is electrically driven to increase the supercharging effect, or electricity is generated utilizing rotation of the turbine shaft to recover electricity from exhaust energy.
• a rotor is heated by an eddy current when the rotary electric machine is operated, the turbine side is exposed to exhaust heat, so that thermal load becomes severe.
• turbosupercharger in which a temperature rise on the side of the stator is detected, and when the temperature exceeds a predetermined value, oil mist is inj ected toward the rotor to cool the same (see Japanese Patent Application Laid-open No. .5-256155).
• a temperature rise on the side of the stator is detected, and when the temperature exceeds a predetermined value, oil mist is inj ected toward the rotor to cool the same
• Japanese Patent Application Laid-open No. .5-256155 When the rotor is exposed to high temperature, there is an adverse possibility that the magnet incorporated in the rotor is demagnetized and the efficiency of the rotary electric machine is deteriorated. Further, since themagnet is made of relatively- brittle material, it is necessary to protect the magnet from centrifugal force caused when the turbine shaft is rotated at high speed especially at high temperature.
• the present invention has been accomplished in view of the above-described circumstances, and it is an object of the invention to provide a turbosupercharger which has a rotary electric machine with high cooling effect on a rotor and high protection effect on a magnet in the rotor, and which is advantageous for allowing the turbine shaft to rotate at high speed.
• a turbosupercharger having a rotary electric machine in which a magnet is disposed on a turbine shaft between a turbine and a compressor impeller so that a rotor of the rotary electric machine is constituted on the turbine shaft, wherein a cylindrical member in which a magnet holder covering the magnet from an outer peripheral side and a sleeve portion to be disposed on an inner periphery of a bearing of the turbine shaft are integrated with each other is provided on the turbine shaft .
• the magnet since the magnet is covered with the magnet holder, even though centrifugal force is applied when the turbine shaft rotates at high speed, the magnet can be restrained on the turbine shaft and thus the magnet can be protected. Since the magnet holder and the sleeve portion are integrated with each other, resistance against thermal conduction between the magnet holder and the sleeve portion is small, so that heat of the rotor is efficiently- released from the magnet holder to the sleeve portion, and that heat transmitted to the sleeve portion can be released using a cooling system of a bearing. Thus, it is possible to enhance the cooling effect on the rotor, andto prevent the heat generation of the rotor.
• the shaft rigidity of the cylindrical member can be enhanced.
• the number of rotation parts to be mounted on the turbine shaft can be reduced. Therefore, when the rotation parts are assembled on the turbine shaft, it is possible to avoid a case in which the shaft is bent due to various errors such as shape error of the rotation parts or assembling error. Accordingly, it is possible to reduce factors which hinder high speed rotation of the turbine, thereby realizing a turbosupercharger having a structure advantageous for increasing the rotation speed.
• the turbosupercharger maybe configured such that lubricating liquid is allowed to be adhered between the sleeve portion and the magnet holder.
• the cooling effect on the rotor can further be enhanced.
• lubricating liquid to be supplied to the bearing can be used as the lubricating liquid to be adhered between the sleeve portion and the magnet holder. If the lubricating liquid for the bearing is used, it is possible to relativelyeasily introduce the lubricating liquid in between the sleeve portion and the magnet holder to utilize cooling of the cylindrical member.
• the cylindrical member may be provided at an outer periphery thereof with a lubricating liquid scattering portion for scattering the lubricating liquid toward a stator of the rotaryelectricmachine by rotation of the rotor.
• a lubricating liquid scattering portion for scattering the lubricating liquid toward a stator of the rotaryelectricmachine by rotation of the rotor.
• an end surface covering portion for covering the magnet from an end surface side thereof may be provided between the magnet holder and the sleeve portion, and the end surface covering portion may be provided with the lubricating liquid scattering portion.
• the rotary- electric machine is set as thinner as possible in terms of efficiency of the rotary electric machine.
• the centrifugal force applied to the magnet holder is increased and reduced repeatedly according to the variation in the revolution number of the turbine shaft, it is necessary to sufficiently secure fatigue strength against the repeated stress .
• the thickness of the magnet holder is as thin as possible and the shape is simplified so that stress concentration is hard to generate.
• the end surface covering portion is disposed on the side of the end surface of the magnet.
• the end surface covering portion is provided with a lubricating liquid scattering portion, it is possible to appropriately set the shape, size or position of the lubricating liquid scattering portion according to a purpose without deteriorating the strength of the cylindrical member, so that the lubricating liquid can be scattered to the rotor effectively. Further, by removing a portion of the end surface covering portion, it is possible to easily adjust the rotation balance (balance of mass around the axis) of a rotation body assembly constituted by the turbine shaft and the rotation parts on the shaft.
• a projection projecting toward an outer periphery of the end surface covering portion may be provided as the lubricating liquid scattering portion .
• lubricating liquid adhered to the surface of the cylindrical member is introduced to the projection by the centrifugal force, and the lubricating liquid can be scattered to a portion around the rotor (preferably to the stator) from the projection.
• the rotation balance of the rotation body assembly can be adjusted.
• the turbosupercharger may further comprise a lubricating liquid path for introducing lubricating liquid to be supplied to the bearing toward the turbine such as to penetrate the turbine shaft .
• a lubricating liquid path for introducing lubricating liquid to be supplied to the bearing toward the turbine such as to penetrate the turbine shaft .
• the cylindrical member in which the magnet holder covering the magnet of the rotor and the sleeve portion of the bearing are integrated with each other is provided on the turbine shaft, it is possible to reliablyprotect themagnet fromthe centrifugal force, to release heat of the rotor to the sleeve portion efficiently to thereby release the heat to the cooling system of the bearing, to reduce the number of the rotation parts to be assembled on the turbine shaft, to enhance shaft rigidity of the rotation body assembly, to prevent the shaft from being bent, thereby realizing the turbosupercharger having structure advantageous for high speed rotation.
• FIG. 1 is a sectional view of a turbosupercharger in its axial direction according to one embodiment of the present invention
• FIG. 2 is a sectional view of a cylindrical member mounted on a turbine shaft and its bearing portions;
• FIG. 3 is a perspective view showing one end of the cylindrical member
• FIG. 4 is a sectional view showing one embodiment in which both sides of the magnet holder of the cylindrical member are provided with projections as lubricating liquid scattering portions;
• FIG. 5 is a view showing one embodiment according to the present invention further comprising a lubricating liquid path for introducing lubricating liquid suppliedto thebearing toward the turbine side.
• FIG. 1 shows one embodiment in which the present invention is applied to a turbosupercharger of an internal combustion engine for an automobile.
• the turbosupercharger 1 includes an exhaust turbine section 2, a compressor section 3 and a rotary electric machine 4 disposed therebetween.
• the exhaust turbine section 2 includes a turbine housing 5 provided such as to constitute a portion of the exhaust passage of the internal combustion engine, and a turbine 6 provided in the turbine housing 5.
• the compressor section 3 includes a compressor housing 7 provided such as to constitute a portion of an intake passage of the internal combustion engine, and an impeller (compressor impeller) 8 provided in the compressor housing 7.
• a bearing housing 9 is provided between the turbine housing 5 and the compressor housing 7.
• the turbine 6 is provided at its one end with a turbine shaft 10 such that the turbine shaft 10 can rotate in unison and cannot separated in the axial direction.
• the turbine shaft 10 penetrates the bearing housing 9, reaches inside of the compressor housing 7, and the impeller 8 is mounted on a tip end of the turbine shaft 10 such that the impeller 8 can rotate in unison.
• the connection structures of the turbine 6, the impeller 8 and the turbine shaft 10 are not limited to those shown in the drawing and the structures may be modified.
• the turbine housing 5, the compressor housing 7 and the bearing housing 9 are constituted as independent parts, and they are combined together to constitute the turbosupercharger housing 11. InFIG. 1, connection positions of the housings 5, 7 and 9 are not clearly shown but they may appropriately be set.
• the rotary electric machine 4 includes a rotor 12 provided on the turbine shaft 10, and a stator 13 provided in the bearing housing 9.
• the rotor 12 is formed by mounting a magnet 14 on an outer periphery of the turbine shaft 10 such that the magnet 14 can rotate in unison with the turbine shaft 10.
• the stator 13 includes a stator core 15 and coil windings 16 disposed on opposite ends of the stator core 15.
• the stator core 15 is disposed such as to surround the magnet 14 from outside, and each of the coil windings 16 is deviated towardthe exhaust turbine section 2 or the compressor section 3 from the magnet 14.
• the bearing housing 9 is provided with a water passage 17 which is closer to the outer periphery than the stator core 15, and cooling water for cooling the turbosupercharger 1 is introduced into the water passage 17.
• a cylindrical member 20 is fitted over an outer periphery of the turbine shaft 10.
• the cylindrical member 20 includes a cylindrical magnet holding tube (magnet holder) 21 covering the magnet 14, and a pair of shaft end tubes 22 which are integrally connected to the magnet holding tube 21 such as to close both ends of the magnet holding tube 21.
• Each shaft end tube 22 includes an end surface covering portion 23 which closes the end of the magnet holding tube 21 and covers the magnet 14 from the end surface side, and a sleeve portion 24 of a small diameter which is integrally connected from the end surface covering portion 23 toward the axially outside.
• the outer diameter of the end surface covering portion 23 is gradually reduced toward the sleeve portion 24.
• the outer peripheral surface of the end surface covering portion 23 is formed into a tapered surface whose diameter is gradually reduced toward the sleeve portion 24, and the sleeve portion 24 is formed into a cylindrical shape of a constant outer diameter.
• the magnet holding tube 21 is integrally connected to the outer periphery of the end surface covering portion 23. It is necessary that the magnet holding tube 21 can withstand the heat generation of the magnet 14, and the magnet holding tube 21 has such high rigidity that the magnet 14 can be held against the centrifugal force caused by high speed rotation of the turbine shaft 10. Accordingly, the magnet holding tube 21 is preferably made of heatproof material such as stainless, titanium or the like.
• the shaft end tube 22 can be made of various pipe materials such as steel tube, and it is preferable that the shaft end tube 22 is made of the material having excellent thermal conductivity and light in weight.
• various connecting method such as welding, brazing or press-fit may be used.
• the end surface covering portion 23 and the sleeve portion 24 may be integrally molded from the same material, or they may be integrally formed by the connecting method such as welding, brazing or press-fit. In any case, in a state where the cylindrical member 20 is incorporated in the turbine shaft 10, the cylindrical member 20 may exist as a single cylindrical component which is integrally provided with the magnet holding tube 21 and at least one of the sleeve portions 24 such that they cannot be disassembled.
• an end of cylindrical member 20 on the side of the turbine 6 butts against an enlarged portion 10a of the turbine shaft 10.
• a thrust collar 25 butts against the end of the cylindrical member 20 on the side of the impeller 8, a seal ring collar 26 and the impeller 8 are mounted in order on the opposite side of the thrust collar 25, the impeller 8 is fastened by a nut 27 in the axial direction, and these rotation parts, i.e., the magnet 14, the cylindrical member 20, the thrust collar 25, the seal ring collar 26 and the impeller 8 are mounted on the turbine shaft 10 such that they can rotate in unison but they cannot move in the axial direction.
• These rotation parts, the turbine 6 and the turbine shaft 10 constitute the rotation body assembly 28 of the turbosupercharger 1.
• Seal rings 30 and 31 are mounted on outer peripheries of the enlarged portion 10a of the turbine shaft 10 and the seal ring collar 26.
• the seal rings 30 and 31 come into contact with the turbosupercharger housing 11 over the entire circumstance. With this, a space between the interior of each of the turbine housing 5 and the compressor housing 7 and an interior of the bearing housing 9 is sealed.
• a disk-like thrust bearing 32 is mounted on the turbosupercharger housing 11. The thrust bearing 32 meshes with the outer periphery of the thrust collar 25, thereby restraining the rotation body assembly 28 from moving in the axial direction with respect to the turbosupercharger housing 11.
• Ring-like bearings 35 are provided in the bearing housing 9 such as to surround the sleeve portions 24 of the cylindrical member 20.
• the bearing 35 on the side of the turbine 6 is sandwitched between a pair of retaining rings 36, thereby restraining the bearing 35 at a fixed position in the axial direction with respect to.
• the bearing housing 9, the bearing 35 on the side of the compressor is sandwitched between the retaining ring 36 and the thrust collar 25, thereby restraining the bearing 35 at a fixed position in the axial direction with respect to the bearing housing 9.
• the inner diameter of each bearing 35 is slightly greater than the outer diameter of each sleeve portion 24. Therefore, there are slight radial gaps between the bearings 35 and the sleeve portions 24. The radial gaps are opened toward the outer periphery of each end surface covering portion 23.
• the bearing housing 9 is formed with lubricating liquid flow paths 40 for introducing lubricating liquid toward the outer periphery of each bearing 35 from the surface of the bearing housing 9.
• Each bearing 35 is formed with a radial through hole 35a (see FIG. 2) which is in communication with the lubricating liquid flow path 40. Therefore, lubricating liquid introduced to the lubricating liquid flow paths 40 are supplied to the gaps between the bearings 35 and the sleeve portions 24 through the through holes 35a, the lubricating liquid forms a film, and thus, the sleeve portions 24 are supported in the radial direction.
• the turbosupercharger housing 11 is further formed with drain paths 41 and 42 for discharging lubricating liquid supplied to the bearings 35.
• the turbosupercharger 1 having the above-described structure, since the magnet 14 is covered with the magnet holding tube 21 of the cylindrical member 20 from the outerperipheryofthemagnet 14 , themagnet 14 is not separated from the turbine shaft 10 by the centrifugal force even if the turbine shaft 10 rotates at high speed, and thus, the magnet 14 can reliably be restrained on the turbine shaft 10. Heat generated in the rotor 12 releases to the sleeve portions 24 from the magnet holding tube 21 through the end surface covering portions 23, and the heat introduced to the sleeve portions 24 are successively eliminated by the lubricating liquid of the bearings 35.
• the magnet holding tube 21, the end surface covering portions 23 and the sleeve portions 24 are integrated with each other, the heat conductivity therebetween is high. Accordingly, heat is less prone to be accumulated in the rotor 12, and cooling efficiency on the rotor 12 is enhanced.
• the gaps between the bearings 35 and the sleeve portions 24 are opened toward the outer periphery of the end surface covering portions 23. Therefore lubricating liquid supplied to the bearings 35 releases to the end surface covering portions 23 and adheres to surfaces thereof, so that the cylindrical member 20 can further be cooled by the adhered lubricating liquid, and that the cooling efficiency on the rotor 12 can further be enhanced.
• the lubricating liquid adhered to the back surfaces of the end surface covering portions 23 moves toward corner portions 23a (see FIG.
• the corner portions 23a of the outer periphery of the end surface covering portions 23 serve as a lubricating liquid scattering portion. Accordingly, the coil windings 16 are also cooled by the lubricating liquid, and heat of the rotary electric machine 4 is further suppressed effectively.
• the cylindrical member 20 has an integrated structure from the magnet holding tube 21 to the sleeve portions 24, the rigidity of the cylindrical member 20 itself is high. As compared with a case where the sleeve portions 24 and the cylindrical member 20 are formed as separate parts and they are assembled on the turbine shaft 10, the number of rotation parts constituting the rotation body assembly 28 is reduced. Since the number of rotationparts is reduced, it is possible to restrain shaft bending due to shape error of the rotation parts (e.g., deviation of perpendicularity of the rotation part end surface with respect to a rotation axis of the turbine shaft 10) or assembling error of the rotation parts. Accordingly, adaptability of the turbosupercharger 1 with respect to the high speed rotation of the turbine shaft 10 can be enhanced.
• the sufficient thickness is secured for the end surface covering portions 23 as compared with the magnet holding tube 21, and thus, if portions of the outer periphery corner portions 23a of the end surface covering portions 23 are provided with notches 23b as shown in FIGS. 2 and 3, the rotation balance of the rotation body assembly 28 can be corrected without deteriorating the strength of the cylindrical member 20. Accordingly, the adaptability of the turbosupercharger 1 with respect to the high speed rotation of the turbine" shaft 10 can further be enhanced.
• the thickness of the magnet holding tube 21 is limited so that a gap between the magnet 14 and the stator core 15 is increased more than necessary.
• the repeated stress is applied to the magnet holding tube 21 because the centrifugal force is increased or reduced according to variation in rotation speed of the turbine shaft 10, it is necessary that the shape of the magnet holding tube 21 is simplified to prevent generation of stress concentration. From such circumferences, limitation is much smaller if the end surface covering portions 23 are provided with the notches 23b as compared with a case where the magnet holding tube 21 is provided with the notches 23b, and the rotation balance can be corrected easily correspondingly.
• the notches 23b are not limited to the corner portions 23a, and it may be provided in appropriate position of the end surface covering portions 23 as shown with broken line in FIG. 3.
• the present invention is not limited to the above described embodiment, andmaybe carried out invariousmodes .
• the end surface covering portion 23 is not limited to the tapered shape, and it may be formed into a disk-like shape having substantially constant thickness in the axial direction as shown in FIG. 4.
• projections 23c may be provided on an outer periphery of the end surface covering portions 23 as the lubricating liquid scattering portion.
• the projections 23c may be continuously provided over the entire circumstance of the end surface covering portions 23, or a plurality of projections 23c may be provided separately from one another in the circumferential direction at appropriate distances fromeach other.
• lubricating liquid adhered to a surface of the cylindrical member 20 can be collected on the projections 23c utilizing the centrifugal force, the lubricating liquid can efficientIybe scatteredtoward the coil windings 16 of the stator 13 to facilitate the cooling operation. If the projections 23c are partly cut, it is possible to easily correct the rotation balance.
• lubricating liquid on the bearings 35 is introduced to the surfaces of the end surface covering portions 23 of the cylindrical member 20 in the above embodiment, lubricating liquid may be introduced to surfaces of the end surface covering portions 23 from a different position.
• FIG. 5 shows an example in which the sleeve portion 24 on the side of the turbine 6 is formed with a through hole 24a extending in the radial direction, and the turbine shaft 10 is provided with a lubricating liquid path 45 for introducing lubricating liquid passing through the through hole 24a toward the turbine 6.
• the lubricating liquid path 45 includes a liquid reservoir groove 45a which makes the circuit of the turbine shaft 10 in the circumferential direction, a first radial passage 45b whose both ends are opened to the liquid reservoir groove 45a, an axial passage 45c which is provided on an axis of the turbine shaft 10 and whose one end is in communication with the through hole 45b, and a second radial passage 45d which is in communication with the axial passage 45c and whose both ends are opened tot he outer periphery of the enlargedportion 10a .
• lubricating liquid on the bearing 35 can cool the end of the turbine shaft 10 on the side of the turbine 6 to thereby suppress heat from being transmitted from the turbine 6 to the rotor 12, and the cooling efficiency of the rotor 12 can further be enhanced.
• the structure of the rotation body assembly 28 described above is only one example, the structure of the rotation body assembly 28 can appropriately be changed as far as the rotation body assembly 28 has the cylindrical member 20 which is integrally formed from the magnet holding tube 21 to at least one of the sleeve portions 24.
• the connection structure % of the turbine 6 and the impeller 8 with respect to the turbine shaft 10 can also be changed appropriately, and the structure for positioning the turbine shaft 10 in the axial direction can also be changed appropriately.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Supercharger (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=36589156

Family Applications (1)

Country Status (4)

Cited By (7)

Families Citing this family (10)

Citations (7)

Family Cites Families (2)

• 2005
  • 2005-04-14 JP JP2005116754A patent/JP4595640B2/ja not_active Expired - Fee Related
• 2006
  • 2006-04-07 DE DE112006000639.8T patent/DE112006000639B4/de not_active Expired - Fee Related
  • 2006-04-07 CN CN2006800120986A patent/CN101160462B/zh not_active Expired - Fee Related
  • 2006-04-07 WO PCT/JP2006/307873 patent/WO2006112372A1/en active Application Filing

Patent Citations (7)

Non-Patent Citations (2)

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